SANTA CRUZ — Authorities at UC Santa Cruz are investigating a swastika found scrawled inside a men’s bathroom last week, as well as three incidents of other hate speech discovered in late October.

The swastika, found by a Jewish student Nov. 9 at Stevenson College, has prompted calls for a strong denouncement from university leaders.

Tammi Rossman-Benjamin, a Jewish studies instructor who for years has charged that UCSC poses a threatening environment for Jewish people, has urged Chancellor George Blumenthal to publicly describe the graffiti as “anti-Semitic.” The student sent a report containing a photo of the swastika to Blumenthal.

“He wanted some public statement that the swastika had appeared and is an anti-Semitic symbol against Jews and Jewish students who would see that,” Rossman-Benjamin said of the student, who the university has not named.

In an email to the student, Associate Chancellor Ashish Sahni pointed to a statement issued by Blumenthal on Nov. 1 reminding the campus about its Principles of Community. That statement came a few days after hate speech was found in men’s bathrooms at Stevenson, Bay Tree Bookstore and in the Humanities building.

“As a university, diversity of thought and the open exchange of ideas are central to our mission,” Blumenthal wrote. “Thankfully, the vast majority of our interactions are respectful. When there are exceptions, such as hateful graffiti, I take pride in how swiftly the overwhelming majority of campus community members condemn such expressions.”

Sahni and UCSC Police Chief Nader Oweis declined to describe the Oct. 26 graffiti in detail but said it did not contain swastikas. Oweis issued a crime alert about that incident and plans to do so for the swastika.

UC President Mark Yudof also replied to the student, who copied him on the report. Yudof cited Blumenthal’s Nov. 1 memo and referenced his own letter to the university’s Jewish community in July, which spelled out UC’s condemnation of hate speech and creation in 2010 of a campus climate reporting system.

“I applaud his leadership in combating anti-Semitism and other abusive behavior,” Yudof wrote of Blumenthal, although Blumenthal has not referred to the Nov. 9 incident as anti-Semitic.

Sahni said no further statement from the chancellor is planned.

“We take any hateful act and hateful symbol seriously,” Sahni said. “This is exactly why the chancellor sent the message out less than a month ago, telling people what the expectations are.”

Another swastika was found in March just as news spread that the U.S. Department of Education’s Office of Civil Rights had opened an investigation into complaints of anti-Semitism filed by Rossman-Benjamin. A representative conducting the probe could not be reached Friday about the status, but the case is still active.

Rossman-Benjamin has documented what she believes is anti-Jewish behavior at UCSC dating back to 2001, including films, teachings and slurs against students. She also alleges the university does not respond as strongly to concerns from Jewish students as it does to victims of other forms of hate speech.

“I really believe there is a real problem, and I believe it because students come and tell me it’s a problem,” Rossman-Benjamin said. “Students have felt seriously harassed and intimidated, and until you can name the thing — it’s anti-Semitism — it’s not going to get addressed.”